dip a toe into

dip into

To spend some of a source of money (such as one's savings).

dip one's toe in

To explore or begin; to enter or get involved in tentatively and for the first time.

head to toe

Entirely; completely; over one's full body.

lucky dip

A selection solely at random.

toe the line

To abide by the rules or conventions; (politics, in particular) to follow the party line.